after reading this thread as well as the discussion about the smoking points of various fats I think I have arrived at some answers, but some questions remain as well:

Answers:
- for all "cold" applications (salad dressings, etc.) olive oil will remain my first choice
- to ensure a sufficient supply of omega-3-fats I will regularly consume walnuts, fish (salmon) and canola oil (according to the manufacturer's website, Rapso, the most popular brand of canola oil in Austria, contains as much as 10% alpha-linolenic acid)
- for frying: don't heat your oil beyond smoking point
- apart from that: try to avoid trans-fats

Questions:
- regarding the omega-3-fats: are flaxseeds (whole or ground) also a significant source of omega-3, i.e. if you add a tablespoon to your breakfast muesli, or would you have to go for the oil to get significant amounts?
- for frying: I read that even at temperatures well below the smoking point polyunsaturated fats will be transformed to trans-fats. Does that happen to an extent that will make olive oil or canola oil unhealthy to use for frying? If so, which would be the better alternative? Does that significantly reduce the amount of omega-3-fat in canola oil, thereby reducing it's benefits?
- and: what is extra-light olive oil? I couldn't find such a thing in Austria - is it some kind of refined olive oil? What about (extra-)virgin olive oil for frying?

Any comments, answers and clarifications would be greatly appreciated,

- regarding the omega-3-fats: are flaxseeds (whole or ground) also a significant source of omega-3, i.e. if you add a tablespoon to your breakfast muesli, or would you have to go for the oil to get significant amounts?

A tablespoon of whole flaxseed will net you about 1/2 the omega-3 oils that a tablespoon of flaxseed oil will - about 3 g. That's still a significant source.

david.mihola wrote:

- for frying: I read that even at temperatures well below the smoking point polyunsaturated fats will be transformed to trans-fats. Does that happen to an extent that will make olive oil or canola oil unhealthy to use for frying? If so, which would be the better alternative? Does that significantly reduce the amount of omega-3-fat in canola oil, thereby reducing it's benefits?

This is true, but the creation of trans fatty acids through heating is very slow. The real concern is the break up of the polyunsaturated chains leading to rancidity and an increasing number of free radicals. This happens more readily with polyunsaturated fats than with mono or saturated. This process happens whenever oil is heated but accelerates after exceeding the smoke point and/or several reheatings. Olive oil and/or canola oil should be fine to use as long as you don't exceed the smoke point (sometimes quite low for extra virgin olive oil - check with your manufacturer) and do not reuse the oil more than once or twice. I prefer to always use fresh oil. (I really like the taste of peanut oil for frying foods and peanut oil has a smoke point generally higher than that of canola or olive... no omega-3's however)

david.mihola wrote:

- and: what is extra-light olive oil? I couldn't find such a thing in Austria - is it some kind of refined olive oil? What about (extra-)virgin olive oil for frying?

Extra-light olive oil is olive oil taht has been refined to remove "impurities". It is a flavorless oil that is yellow in color and tastes like - well oil (kind of like canola). Because of the removal of impurities and free acids, the oil is more resistant to heat (generally exceeding 450°F). Extra virgin olive oil is less refined (intentionally preserving the flavor of the olive fruit) and therefore will leave your food tasting a little like the oil (which is desireable in some applicationa nd not in others). Because of the free acids in EVOO (as the hip chef's on TV like to say), it tends to have a much lower smoke point - closer to 320°F. However, many brands of high quality EVOO (like Bertolli) have smoke points of above 400°F making them suitable for frying applications.

sorry, completely forgot to check back for replies - thank you very much for your quick and detailed answer!

Greetings, David

P.S.: Just for the record: after looking a bit more, I was able to find an olive oil with a higher smoking point in our supermarkets - it's also advertised as being specially suited for baking and frying.

to the people that say "cholesterol is bad because people with heart disease have high cholesterol", that correlation does not prove that ingesting cholesterol is bad. its like saying water is unhealthy because people that drown have water in their lungs.

there is something going on in the body that deposits plaque on artery walls. but no one knows definitively what that is yet.

history makes me weary of claims of what is good and bad for me. for years, eggs and butter were good, then they were bad, then margarine was good, now its bad, now eggs and butter are good again...

my opinion is that eating natural foods and getting regular exercise are enough to stay healthy - or as healthy as can be expected based on genetic history (that's the engineer in me talking).

Well, this is my first visit to this site. I found Michael's article to be very interesting and somewhat familiar. When I was 25 my doctor told me that my cholesterol was abnormally high and that I needed to reduce it by diet. I have tried most of my life to lower my cholesterol by diet, but it does not work well, but it does make a difference in lipid levels proven by blood tests. I have taken a variety of statin medications and bile sequestors, but end up feeling achey and tired and I would become ill very easily. Every time I lowered my cholesterol levels and did not feel well, I would discontinue the statins and other cholesterol medications. I immediately began to feel better without them and I was able to maintain my health easily. Finally I took a statin that harmed my liver and produced very high levels of CPK. I was ill and felt like I was going to die and thankfully discontinue taking it. That was over ten years ago. It took me a few years to recover from the muscle damage, but I feel like I am flexible again. Now at age 65+ my cholesterol is well over 440. I try to eat healthy foods. I wonder every day if I will have a heart attack any time soon and hope I do not, but I feel fine. If it is the amount of cholesterol in our blood that causes heart attacks, I think I would have had one by now. I am afraid to resume taking any statin medications. I know other people with very high levels and they are doing fine also. I think it is life style that is the major problem. I cook most of my food from fresh ingredients. I do eat meat and eggs but everything is small amounts, nothing to the extreme. Any ideas on what to do besides give up all sugar? I also think that it is a major problem in one's diet.
Comments, suggestions?

Hi Michael, great article! There is one thing I would like to know - and it might be off topic - but I'm hoping there will be a medical student or someone knowledgeable in this area who can answer. In all the reading I have done on this topic I cannot find a definitve explanation on how the body metabolises saturated fats vs poly or mono fats.

That is, what is the pathway that the metabolism of saturated fats takes that allegedly raises "bad" cholesterol levels and "causes heart disease", as opposed to the pathway that poly or mono fats takes? If one type of fat's metabolism causes all this "damage" and the other's don't, surely these different types of fat are metabolised by the body differently?...or am I simplyifying things too much?

All the literature I have read about this topic only refers to "fats" in general. Maybe all fats are metabolised the same way and the bad rap that saturated fats get continues to be clouded by the big pharmaceutical companies?? Interested in anyone's thoughts on this...

processed seed oils were not around 100 years ago when people on average ate 3 eggs a day. myocardial infarction as a term didnt exist but big agro businesses were booming and corn and soybean industries created the myth of bad saturated fats/good polyunsaturated, in fact some corn crony scientist was trying to push for at least a cup of corn oil a day as recommendations. I was first turned on to the bullsh!t about villanized sat. fats by my uncle who since a triple bypass 6 years ago and a diagnosis of less than two years to live, eats as much butter and coconut oil as he can everyday. It's the fascist trifecta, big agro-business, the FDA, and big-Pharm. Most of the theories that the lipid hypothesis is based upon are almost a hundred years old. Like the last guy said "if it wasnt a food 100 years...." well said.

I buy butter from an Indian grocer under he brand name "AMul". You can ask them for amul butter and they might have it. It isn't at all stores though. It might also be carried in pakistani stores or some middle eastern grocers stores. It is wonderful tasting and I don't believe it's pasteurized. I have not found a butter made like this in the usa. It could be because indians treat their cows with love:-)

That said, I do avoid eating a lot of saturated fats simply because that is what my nutritionist recommends while she particulary recommends unrefined organic coconut oil: she does her research. But all things in moderation is the safe bet until the dust settles; while I love the articles on this site I generally don't get into the details so much.

Hello Michael, I can't help but notice you are using canola oil. Canola oil becomes rancid very quickly, has high linoleic acid content (linoleic was used as an immunosuppressor for kidney transplant patients, if that's not bad enough, they were forced to stop using it as patients had a disproportionately high cancer rate). It seems the canola oil may be fueling the inflammation, and putting your arteries at a greater risk even though cholesterol isnt the real problem. You've probably researched this and changed your diet by now, but I dont think you should be recommending canola oil at all.

An unsaturated fatty acid, C17H31COOH, considered essential to the human diet, that is an important component of drying oils, such as linseed oil.
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Some mistaken websites contend that canola oil is toxic to man and animal alike. This is unequivocally false. Years of published studies in laboratory animals and humans have shown it to be nutritious and safe, and it is recognized as such by regulatory and health agencies around the world.
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Health considerations

Canola oil is rich in oleic acid (an omega-9 fatty acid that is about 60% of the oil), has significant levels of the essential linoleic acid (an omega-6 fatty acid that is about 19% of the oil) and beneficial levels of the omega-3 linolenic acid (9% of the total). The oil is also reported to be rich in vitamin E (alpha and gamma tocopherols), vitamin K (as K1; phylloquinone) and have measurable levels of phytosterols such as stigmasterol, campesterol and beta-sitosterol (US Department of Agriculture, 2009). There are also specialty varieties with elevated levels of oleic acid (70%) to improve shelf life, or enriched with gamma-linolenic acid (GLA, a special omega-6 fatty acid) as an option to borage or evening primrose oil.
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Linoleic acid is a member of the group of essential fatty acids called omega-6 fatty acids, so called because they are an essential dietary requirement for all mammals. The other group of essential fatty acids is the omega-3 fatty acids, for example Alpha-linolenic acid. Omega-6 deficiency symptoms include dry hair, hair loss,[2] and poor wound healing.[3]
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Possible Roles in Disease

Cancer Prevention

A study in mice has shown that dietary intake of Conjugated Linoleic Acid (CLA) can help prevent cancer in mice. The study looked at a specific isomer of LA and studied its effect on cancer induced by dimethylbenz(a)anthracene. The study suggested a significant effect of CLA intake on the reduction of carcinogenesis. [8]

Cystic fibrosis

Since children with cystic fibrosis suffer from Essential Fatty Acid Deficiency due to malabsorption, it was hypothesized that high doses of LA might aid in their growth. The study looked at two groups of infants with cystic fibrosis on diets with two different levels of LA. It was shown that supplementary LA, indeed, has a positive effect on the growth of infants with cystic fibrosis, especially between 6 and 9 months of age.[9]

Dermatitis

Dermatitis is one of the first signs of an Essential Fatty Acid deficiency in both humans and animals. Until 1955, one of the most widely applied treatments for atopic eczema was a high dose of GLA. [10]

Diabetes

A number of studies have shown that diabetics require higher than normal intakes of LA. Because diabetics have consistently been shown to have above normal levels of LA while having lower than normal levels of GLA, it is believed that diabetics have impaired Δ-6-desaturase activity. Increased intakes of LA have been shown to attenuate diabetic complications in numerous studies.[11]
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